Currently rules are calculated in the moment when the user queries the data.
It would be great to have the option to shift the timing to the point when the user changes data. So the result of the calculation would be stored/persisted when the user changes a certain parameter.
-> in this moment the change would only affect tiny slices of the cube,
related to the parameters of the calculation. (a bit like a SVS routine)
Generaly this could help to optimize performance in scenarios where reporting performance is critical but data entry performance not that much.
In relational databases this is known as "materialized views".
Right know I sometimes use ETL, mirror cubes or SVS for such things.
But this always generates additional overhead and maintenance.